/**
 * @file
 * netconn API (to be used from non-TCPIP threads)
 */

/*
 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * This file is part of the lwIP TCP/IP stack.
 *
 * Author: Adam Dunkels <adam@sics.se>
 *
 */
#ifndef LWIP_HDR_API_H
#define LWIP_HDR_API_H

#include "lwip/opt.h"

#if LWIP_NETCONN || LWIP_SOCKET /* don't build if not configured for use in lwipopts.h */
/* Note: Netconn API is always available when sockets are enabled -
 * sockets are implemented on top of them */

#include "lwip/arch.h"
#include "lwip/netbuf.h"
#include "lwip/sys.h"
#include "lwip/ip_addr.h"
#include "lwip/err.h"

#ifdef __cplusplus
extern "C"
{
#endif

/* Throughout this file, IP addresses and port numbers are expected to be in
 * the same byte order as in the corresponding pcb.
 */

/* Flags for netconn_write (u8_t) */
#define NETCONN_NOFLAG    0x00
#define NETCONN_NOCOPY    0x00 /* Only for source code compatibility */
#define NETCONN_COPY      0x01
#define NETCONN_MORE      0x02
#define NETCONN_DONTBLOCK 0x04
#define NETCONN_NOAUTORCVD                                                                                             \
    0x08                   /* prevent netconn_recv_data_tcp() from updating the tcp window - must be done manually via \
                              netconn_tcp_recvd() */
#define NETCONN_NOFIN 0x10 /* upper layer already received data, leave FIN in queue until called again */

/* Flags for struct netconn.flags (u8_t) */
/** This netconn had an error, don't block on recvmbox/acceptmbox any more */
#define NETCONN_FLAG_MBOXCLOSED 0x01
/** Should this netconn avoid blocking? */
#define NETCONN_FLAG_NON_BLOCKING 0x02
/** Was the last connect action a non-blocking one? */
#define NETCONN_FLAG_IN_NONBLOCKING_CONNECT 0x04
#if LWIP_NETCONN_FULLDUPLEX
    /** The mbox of this netconn is being deallocated, don't use it anymore */
#define NETCONN_FLAG_MBOXINVALID 0x08
#endif /* LWIP_NETCONN_FULLDUPLEX */
/** If a nonblocking write has been rejected before, poll_tcp needs to
    check if the netconn is writable again */
#define NETCONN_FLAG_CHECK_WRITESPACE 0x10
#if LWIP_IPV6
/** If this flag is set then only IPv6 communication is allowed on the
    netconn. As per RFC#3493 this features defaults to OFF allowing
    dual-stack usage by default. */
#define NETCONN_FLAG_IPV6_V6ONLY 0x20
#endif /* LWIP_IPV6 */
#if LWIP_NETBUF_RECVINFO
/** Received packet info will be recorded for this netconn */
#define NETCONN_FLAG_PKTINFO 0x40
#endif /* LWIP_NETBUF_RECVINFO */
/** A FIN has been received but not passed to the application yet */
#define NETCONN_FIN_RX_PENDING 0x80

/* Helpers to process several netconn_types by the same code */
#define NETCONNTYPE_GROUP(t)    ((t) & 0xF0)
#define NETCONNTYPE_DATAGRAM(t) ((t) & 0xE0)
#if LWIP_IPV6
#define NETCONN_TYPE_IPV6            0x08
#define NETCONNTYPE_ISIPV6(t)        (((t) & NETCONN_TYPE_IPV6) != 0)
#define NETCONNTYPE_ISUDPLITE(t)     (((t) & 0xF3) == NETCONN_UDPLITE)
#define NETCONNTYPE_ISUDPNOCHKSUM(t) (((t) & 0xF3) == NETCONN_UDPNOCHKSUM)
#else /* LWIP_IPV6 */
#define NETCONNTYPE_ISIPV6(t)        (0)
#define NETCONNTYPE_ISUDPLITE(t)     ((t) == NETCONN_UDPLITE)
#define NETCONNTYPE_ISUDPNOCHKSUM(t) ((t) == NETCONN_UDPNOCHKSUM)
#endif /* LWIP_IPV6 */

    /** @ingroup netconn_common
     * Protocol family and type of the netconn
     */
    enum netconn_type
    {
        NETCONN_INVALID = 0,
        /** TCP IPv4 */
        NETCONN_TCP = 0x10,
#if LWIP_IPV6
        /** TCP IPv6 */
        NETCONN_TCP_IPV6 = NETCONN_TCP | NETCONN_TYPE_IPV6 /* 0x18 */,
#endif /* LWIP_IPV6 */
        /** UDP IPv4 */
        NETCONN_UDP = 0x20,
        /** UDP IPv4 lite */
        NETCONN_UDPLITE = 0x21,
        /** UDP IPv4 no checksum */
        NETCONN_UDPNOCHKSUM = 0x22,

#if LWIP_IPV6
        /** UDP IPv6 (dual-stack by default, unless you call @ref netconn_set_ipv6only) */
        NETCONN_UDP_IPV6 = NETCONN_UDP | NETCONN_TYPE_IPV6 /* 0x28 */,
        /** UDP IPv6 lite (dual-stack by default, unless you call @ref netconn_set_ipv6only) */
        NETCONN_UDPLITE_IPV6 = NETCONN_UDPLITE | NETCONN_TYPE_IPV6 /* 0x29 */,
        /** UDP IPv6 no checksum (dual-stack by default, unless you call @ref netconn_set_ipv6only) */
        NETCONN_UDPNOCHKSUM_IPV6 = NETCONN_UDPNOCHKSUM | NETCONN_TYPE_IPV6 /* 0x2a */,
#endif /* LWIP_IPV6 */

        /** Raw connection IPv4 */
        NETCONN_RAW = 0x40
#if LWIP_IPV6
            /** Raw connection IPv6 (dual-stack by default, unless you call @ref netconn_set_ipv6only) */
            ,
        NETCONN_RAW_IPV6 = NETCONN_RAW | NETCONN_TYPE_IPV6 /* 0x48 */
#endif                                                     /* LWIP_IPV6 */
    };

    /** Current state of the netconn. Non-TCP netconns are always
     * in state NETCONN_NONE! */
    enum netconn_state
    {
        NETCONN_NONE,
        NETCONN_WRITE,
        NETCONN_LISTEN,
        NETCONN_CONNECT,
        NETCONN_CLOSE
    };

    /** Used to inform the callback function about changes
     *
     * Event explanation:
     *
     * In the netconn implementation, there are three ways to block a client:
     *
     * - accept mbox (sys_arch_mbox_fetch(&conn->acceptmbox, &accept_ptr, 0); in netconn_accept())
     * - receive mbox (sys_arch_mbox_fetch(&conn->recvmbox, &buf, 0); in netconn_recv_data())
     * - send queue is full (sys_arch_sem_wait(LWIP_API_MSG_SEM(msg), 0); in lwip_netconn_do_write())
     *
     * The events have to be seen as events signaling the state of these mboxes/semaphores. For non-blocking
     * connections, you need to know in advance whether a call to a netconn function call would block or not,
     * and these events tell you about that.
     *
     * RCVPLUS events say: Safe to perform a potentially blocking call call once more.
     * They are counted in sockets - three RCVPLUS events for accept mbox means you are safe
     * to call netconn_accept 3 times without being blocked.
     * Same thing for receive mbox.
     *
     * RCVMINUS events say: Your call to to a possibly blocking function is "acknowledged".
     * Socket implementation decrements the counter.
     *
     * For TX, there is no need to count, its merely a flag. SENDPLUS means you may send something.
     * SENDPLUS occurs when enough data was delivered to peer so netconn_send() can be called again.
     * A SENDMINUS event occurs when the next call to a netconn_send() would be blocking.
     */
    enum netconn_evt
    {
        NETCONN_EVT_RCVPLUS,
        NETCONN_EVT_RCVMINUS,
        NETCONN_EVT_SENDPLUS,
        NETCONN_EVT_SENDMINUS,
        NETCONN_EVT_ERROR
    };

#if LWIP_IGMP || (LWIP_IPV6 && LWIP_IPV6_MLD)
    /** Used for netconn_join_leave_group() */
    enum netconn_igmp
    {
        NETCONN_JOIN,
        NETCONN_LEAVE
    };
#endif /* LWIP_IGMP || (LWIP_IPV6 && LWIP_IPV6_MLD) */

#if LWIP_DNS
/* Used for netconn_gethostbyname_addrtype(), these should match the DNS_ADDRTYPE defines in dns.h */
#define NETCONN_DNS_DEFAULT   NETCONN_DNS_IPV4_IPV6
#define NETCONN_DNS_IPV4      0
#define NETCONN_DNS_IPV6      1
#define NETCONN_DNS_IPV4_IPV6 2 /* try to resolve IPv4 first, try IPv6 if IPv4 fails only */
#define NETCONN_DNS_IPV6_IPV4 3 /* try to resolve IPv6 first, try IPv4 if IPv6 fails only */
#endif                          /* LWIP_DNS */

    /* forward-declare some structs to avoid to include their headers */
    struct ip_pcb;
    struct tcp_pcb;
    struct udp_pcb;
    struct raw_pcb;
    struct netconn;
    struct api_msg;

    /** A callback prototype to inform about events for a netconn */
    typedef void (*netconn_callback)(struct netconn*, enum netconn_evt, u16_t len);

    /** A netconn descriptor */
    struct netconn
    {
        /** type of the netconn (TCP, UDP or RAW) */
        enum netconn_type type;
        /** current state of the netconn */
        enum netconn_state state;
        /** the lwIP internal protocol control block */
        union {
            struct ip_pcb* ip;
            struct tcp_pcb* tcp;
            struct udp_pcb* udp;
            struct raw_pcb* raw;
        } pcb;
        /** the last asynchronous unreported error this netconn had */
        err_t pending_err;
#if !LWIP_NETCONN_SEM_PER_THREAD
        /** sem that is used to synchronously execute functions in the core context */
        sys_sem_t op_completed;
#endif
        /** mbox where received packets are stored until they are fetched
            by the netconn application thread (can grow quite big) */
        sys_mbox_t recvmbox;
#if LWIP_TCP
        /** mbox where new connections are stored until processed
            by the application thread */
        sys_mbox_t acceptmbox;
#endif /* LWIP_TCP */
#if LWIP_NETCONN_FULLDUPLEX
        /** number of threads waiting on an mbox. This is required to unblock
            all threads when closing while threads are waiting. */
        int mbox_threads_waiting;
#endif
        /** only used for socket layer */
#if LWIP_SOCKET
        int socket;
#endif /* LWIP_SOCKET */
#if LWIP_SO_SNDTIMEO
        /** timeout to wait for sending data (which means enqueueing data for sending
            in internal buffers) in milliseconds */
        s32_t send_timeout;
#endif /* LWIP_SO_RCVTIMEO */
#if LWIP_SO_RCVTIMEO
        /** timeout in milliseconds to wait for new data to be received
            (or connections to arrive for listening netconns) */
        u32_t recv_timeout;
#endif /* LWIP_SO_RCVTIMEO */
#if LWIP_SO_RCVBUF
        /** maximum amount of bytes queued in recvmbox
            not used for TCP: adjust TCP_WND instead! */
        int recv_bufsize;
        /** number of bytes currently in recvmbox to be received,
            tested against recv_bufsize to limit bytes on recvmbox
            for UDP and RAW, used for FIONREAD */
        int recv_avail;
#endif /* LWIP_SO_RCVBUF */
#if LWIP_SO_LINGER
        /** values <0 mean linger is disabled, values > 0 are seconds to linger */
        s16_t linger;
#endif /* LWIP_SO_LINGER */
        /** flags holding more netconn-internal state, see NETCONN_FLAG_* defines */
        u8_t flags;
#if LWIP_TCP
        /** TCP: when data passed to netconn_write doesn't fit into the send buffer,
            this temporarily stores the message.
            Also used during connect and close. */
        struct api_msg* current_msg;
#endif /* LWIP_TCP */
        /** A callback function that is informed about events for this netconn */
        netconn_callback callback;
    };

    /** This vector type is passed to @ref netconn_write_vectors_partly to send
     * multiple buffers at once.
     * ATTENTION: This type has to directly map struct iovec since one is casted
     *            into the other!
     */
    struct netvector
    {
        /** pointer to the application buffer that contains the data to send */
        const void* ptr;
        /** size of the application data to send */
        size_t len;
    };

/** Register an Network connection event */
#define API_EVENT(c, e, l)       \
    if (c->callback)             \
    {                            \
        (*c->callback)(c, e, l); \
    }

/* Network connection functions: */

/** @ingroup netconn_common
 * Create new netconn connection
 * @param t @ref netconn_type */
#define netconn_new(t)                  netconn_new_with_proto_and_callback(t, 0, NULL)
#define netconn_new_with_callback(t, c) netconn_new_with_proto_and_callback(t, 0, c)
    struct netconn* netconn_new_with_proto_and_callback(enum netconn_type t, u8_t proto, netconn_callback callback);
    err_t netconn_prepare_delete(struct netconn* conn);
    err_t netconn_delete(struct netconn* conn);
/** Get the type of a netconn (as enum netconn_type). */
#define netconn_type(conn) (conn->type)

    err_t netconn_getaddr(struct netconn* conn, ip_addr_t* addr, u16_t* port, u8_t local);
/** @ingroup netconn_common */
#define netconn_peer(c, i, p) netconn_getaddr(c, i, p, 0)
/** @ingroup netconn_common */
#define netconn_addr(c, i, p) netconn_getaddr(c, i, p, 1)

    err_t netconn_bind(struct netconn* conn, const ip_addr_t* addr, u16_t port);
    err_t netconn_bind_if(struct netconn* conn, u8_t if_idx);
    err_t netconn_connect(struct netconn* conn, const ip_addr_t* addr, u16_t port);
    err_t netconn_disconnect(struct netconn* conn);
    err_t netconn_listen_with_backlog(struct netconn* conn, u8_t backlog);
/** @ingroup netconn_tcp */
#define netconn_listen(conn) netconn_listen_with_backlog(conn, TCP_DEFAULT_LISTEN_BACKLOG)
    err_t netconn_accept(struct netconn* conn, struct netconn** new_conn);
    err_t netconn_recv(struct netconn* conn, struct netbuf** new_buf);
    err_t netconn_recv_udp_raw_netbuf(struct netconn* conn, struct netbuf** new_buf);
    err_t netconn_recv_udp_raw_netbuf_flags(struct netconn* conn, struct netbuf** new_buf, u8_t apiflags);
    err_t netconn_recv_tcp_pbuf(struct netconn* conn, struct pbuf** new_buf);
    err_t netconn_recv_tcp_pbuf_flags(struct netconn* conn, struct pbuf** new_buf, u8_t apiflags);
    err_t netconn_tcp_recvd(struct netconn* conn, size_t len);
    err_t netconn_sendto(struct netconn* conn, struct netbuf* buf, const ip_addr_t* addr, u16_t port);
    err_t netconn_send(struct netconn* conn, struct netbuf* buf);
    err_t netconn_write_partly(
        struct netconn* conn,
        const void* dataptr,
        size_t size,
        u8_t apiflags,
        size_t* bytes_written);
    err_t netconn_write_vectors_partly(
        struct netconn* conn,
        struct netvector* vectors,
        u16_t vectorcnt,
        u8_t apiflags,
        size_t* bytes_written);
/** @ingroup netconn_tcp */
#define netconn_write(conn, dataptr, size, apiflags) netconn_write_partly(conn, dataptr, size, apiflags, NULL)
    err_t netconn_close(struct netconn* conn);
    err_t netconn_shutdown(struct netconn* conn, u8_t shut_rx, u8_t shut_tx);

#if LWIP_IGMP || (LWIP_IPV6 && LWIP_IPV6_MLD)
    err_t netconn_join_leave_group(
        struct netconn* conn,
        const ip_addr_t* multiaddr,
        const ip_addr_t* netif_addr,
        enum netconn_igmp join_or_leave);
    err_t netconn_join_leave_group_netif(
        struct netconn* conn,
        const ip_addr_t* multiaddr,
        u8_t if_idx,
        enum netconn_igmp join_or_leave);
#endif /* LWIP_IGMP || (LWIP_IPV6 && LWIP_IPV6_MLD) */
#if LWIP_DNS
#if LWIP_IPV4 && LWIP_IPV6
    err_t netconn_gethostbyname_addrtype(const char* name, ip_addr_t* addr, u8_t dns_addrtype);
#define netconn_gethostbyname(name, addr) netconn_gethostbyname_addrtype(name, addr, NETCONN_DNS_DEFAULT)
#else /* LWIP_IPV4 && LWIP_IPV6 */
    err_t netconn_gethostbyname(const char* name, ip_addr_t* addr);
#define netconn_gethostbyname_addrtype(name, addr, dns_addrtype) netconn_gethostbyname(name, addr)
#endif /* LWIP_IPV4 && LWIP_IPV6 */
#endif /* LWIP_DNS */

    err_t netconn_err(struct netconn* conn);
#define netconn_recv_bufsize(conn) ((conn)->recv_bufsize)

#define netconn_set_flags(conn, set_flags)                   \
    do                                                       \
    {                                                        \
        (conn)->flags = (u8_t)((conn)->flags | (set_flags)); \
    } while (0)
#define netconn_clear_flags(conn, clr_flags)                                 \
    do                                                                       \
    {                                                                        \
        (conn)->flags = (u8_t)((conn)->flags & (u8_t)(~(clr_flags) & 0xff)); \
    } while (0)
#define netconn_is_flag_set(conn, flag) (((conn)->flags & (flag)) != 0)

/** Set the blocking status of netconn calls (@todo: write/send is missing) */
#define netconn_set_nonblocking(conn, val)                        \
    do                                                            \
    {                                                             \
        if (val)                                                  \
        {                                                         \
            netconn_set_flags(conn, NETCONN_FLAG_NON_BLOCKING);   \
        }                                                         \
        else                                                      \
        {                                                         \
            netconn_clear_flags(conn, NETCONN_FLAG_NON_BLOCKING); \
        }                                                         \
    } while (0)
/** Get the blocking status of netconn calls (@todo: write/send is missing) */
#define netconn_is_nonblocking(conn) (((conn)->flags & NETCONN_FLAG_NON_BLOCKING) != 0)

#if LWIP_IPV6
/** @ingroup netconn_common
 * TCP: Set the IPv6 ONLY status of netconn calls (see NETCONN_FLAG_IPV6_V6ONLY)
 */
#define netconn_set_ipv6only(conn, val)                          \
    do                                                           \
    {                                                            \
        if (val)                                                 \
        {                                                        \
            netconn_set_flags(conn, NETCONN_FLAG_IPV6_V6ONLY);   \
        }                                                        \
        else                                                     \
        {                                                        \
            netconn_clear_flags(conn, NETCONN_FLAG_IPV6_V6ONLY); \
        }                                                        \
    } while (0)
/** @ingroup netconn_common
 * TCP: Get the IPv6 ONLY status of netconn calls (see NETCONN_FLAG_IPV6_V6ONLY)
 */
#define netconn_get_ipv6only(conn) (((conn)->flags & NETCONN_FLAG_IPV6_V6ONLY) != 0)
#endif /* LWIP_IPV6 */

#if LWIP_SO_SNDTIMEO
/** Set the send timeout in milliseconds */
#define netconn_set_sendtimeout(conn, timeout) ((conn)->send_timeout = (timeout))
/** Get the send timeout in milliseconds */
#define netconn_get_sendtimeout(conn) ((conn)->send_timeout)
#endif /* LWIP_SO_SNDTIMEO */
#if LWIP_SO_RCVTIMEO
/** Set the receive timeout in milliseconds */
#define netconn_set_recvtimeout(conn, timeout) ((conn)->recv_timeout = (timeout))
/** Get the receive timeout in milliseconds */
#define netconn_get_recvtimeout(conn) ((conn)->recv_timeout)
#endif /* LWIP_SO_RCVTIMEO */
#if LWIP_SO_RCVBUF
/** Set the receive buffer in bytes */
#define netconn_set_recvbufsize(conn, recvbufsize) ((conn)->recv_bufsize = (recvbufsize))
/** Get the receive buffer in bytes */
#define netconn_get_recvbufsize(conn) ((conn)->recv_bufsize)
#endif /* LWIP_SO_RCVBUF*/

#if LWIP_NETCONN_SEM_PER_THREAD
    void netconn_thread_init(void);
    void netconn_thread_cleanup(void);
#else /* LWIP_NETCONN_SEM_PER_THREAD */
#define netconn_thread_init()
#define netconn_thread_cleanup()
#endif /* LWIP_NETCONN_SEM_PER_THREAD */

#ifdef __cplusplus
}
#endif

#endif /* LWIP_NETCONN || LWIP_SOCKET */

#endif /* LWIP_HDR_API_H */
